Dust collector for commutator grinders



l2, 1957 W, G, SCHlNsKE 23,?84-,537

DUST COLLECTOR FOR COMMUTATOR GRINDERS Filed Nov. 8, 1954 3 Sheets-Sheetl l March 12, 1957 w. G. scHlNsKE 2,784,537

DUST COLLECTOR FOR COMMUTATOR GRINDERS Filed NOV. 8, 1954 3 Sheets-Sheet 2 'March 12, 1957 w. G. scHlNsKE OusT COLLECTOR FOR COMMUTATOR GRINOERS 3 Sheets-Sheet 3 Filed NOV. 8, 1954 United States Patent O DUST COLLECTOR FOR COMMUTATOR GRINDERS William G. Schinske, Sycamore, Ill., assignor to Ideal Industries, Inc., Sycamore, Ill., a corporation of Delaware Application November 8, 1954, Serial No. 467,456

8 Claims. (Cl. 51244) My invention is in the field of commutator grinding, methods of grinding commutatore, and apparatuses for doing it.

A primary object of my invention is a new and improved commutator grinder apparatus which prevents the copper duct created during the grinding operation from being blown out into adjacent areas.

Another object of my invention is a commutator grinder mechanism which is much simpler and far more pleasant to operate for the user in that the copper dust created during the grinding operation is immediately funneled away in a suction device.

Another object of my invention is a dust collector for a commutator `grinder unit which prevents the dust from getting into adjacent apparatus and causing shorts in the commutator brushes and the like.

Another object of my invention is a new and improved method of grinding commutatore.

Another object of my invention is a dust collecting unit for a commutator grinder which is easy to use, very eicient in operation, and which materially simplifies the commutator grinding operation.

Another object of my invention is a commutator grinder and dust collector which is easier to operate in that it reduces the discomfort of the operator.

Other objects will appear from time to time in the ensuing specication and drawings in which:

Figure l is a perspective view of my invention on a conventional commutator;

Figure 2 is a perspective view on a large scale, showing the details of the commutator grinder and dust collector, with parts removed; and

Figure 3 is a side view partly in section of the apparatus shown in Figure 2.

In Figure l the housing or cylindrical frame has been indicated generally at 10, and it should be understood that this is a schematic representation of a locomotive frame, the frame of a power plant installation, or the like. It could be any motor or generator unit with large commutaors. The housing is provided with a port or opening 12 which is normally closed by a removable panel, but as shown in Figure l the panel has been removed to gain access to a cylindrical commutator 14 which is mounted on the shaft of the generator or motor not shown. Conventional commutator brush units 16 are mounted in brush blocks 18 on the housing.

As shown in Figure 1, one of the brush units has been removed and a grinding unit, indicated generally at 20, has been secured in the blocks. This grinding unit is composed of a grinder support 22 which is removably mounted on a pair of rods 24 which fit in the brush blocks. The forward face 26 of the support is relatively at and one or more openings are provided at 28 to receive bolts 30 which thread into the base 32 of a stone carriage 34.

The stone .carriage tits on the upper surface of the base and is adapted for longitudinal movement through a dove- "ice tail slot connection as at 36. A cross slide 38 is mounted on the top surface of the carriage through a dovetail slot connection and is adapted to move in a longitudinal direction toward and away from the commutator. This direction is at right angles to the directional movement of the carriage relative to the base.

Handles or any suitable actuating means are provided to move the carriage horizontally across the commutator as well as longitudinally toward it. Specifically a carriage bracket 40 is mounted on the front of the carriage 34 by suitable bolts 42 and has a sleeve 44 which rotatably receives a shaft 46 which has a hand wheel 48 at its outer end. A pinion 50 is mounted on the other end of the shaft below the sleeve and engages a rack 52 iixed on the forward edge of the base 32. Thus, upon rotation of this hand wheel the rotating pinion will move back and forth under the stationary rack 52 and will carry the carriage 34 with it. The top end of the bracket has an opening or sleeve 53 which carries a shaft 54 hav ing a hand wheel 55 at its outer end. The other end of the shaft is threaded at 56 and projects into and threadably engages a threaded transverse opening 58 in the cross slide 59. Thus, upon rotation of this hand wheel, bracket 40 will hold the shaft 52 stationary while the cross slide will move in or out.

The hand Wheel 48 gives horizontal movement to the carriage while the hand wheel 5S gives it longitudinal movement.

A suitable grinding stone 60 is mounted on the top of the cross slide and is secured by clamps 62 which are pulled down on the stone by suitable bolts 64 that are threaded into the top of the cross slide in a suitable manner.

The operation of this mechanism is as follows: Rotation of the hand wheel 4S will traverse the stone across the commutator while rotation of the hand wheel 55 will regulate the approach of the stone to the commutator. Thus the user, after setting the stone and. rmly clamping it in place, will iirst move the stone inwardly into engagement with the commutator by operating the hand wheel 55 and he will then oscillate the stone back and forth by rotating the hand wheel 48, lirst in one direction and then in the other.

To prevent copper dust from the stone from flying into the motor, the generator, or the like, and all over the adjoining area, I have positioned a nozzle mechanism indicated generally at 66 ahead of or beyond the grinding unit. This nozzle mechanism includes a swivel nozzle 68 pivoted to a swivel arm 70 on a stud 72 secured at one end by a suitable nut 74 and at the other by suitable wing nut 76. The nozzle ares out in each direction as at 78 in Figure 2, although the other side cannot be seen. The flared portion carries a depending longitudinal brush 8i) surrounded by a rubber strip 82 dening 1ongitudinal openings 84 and 86 on each side of the brush. It will be understood that the brush extends from one side to the other and divides the longitudinal opening in the end of the nozzle into two parallel slots. These slots or openings lead through passages inside the nozzle through the upper portion around the studs 72 across the swivel arm 70, with any suitable gasket being provided between the mating portions of these two parts, to a suitable flexible hose or tube 88 which is secured to the swivel arm by a suitable joint 90. The tubular hose leads to a conventional commercial suction vacuum cleaner unit 92 which has the usual dust collector bag 94 and handle mechanism 96. The cleaner may be mounted removably on the frame of the motor unit or otherwise suitably supported.

The nozzle structure is held in place ahead of or beyond the stone by a suitable attaching mechanism 98 which includes a stud 100 screwed into the upper end of the grinder support with a clamp 102 surrounding the stud and connected to a bar 104 which has a clamp 106 on its other end. This clamp also is connected .to the nozzle stud 72. The clamp 102 is tightened or loosened by a handle 108 while the clamp 106 is actuated by a handle 110.

The use, operation and function of my invention are as follows:

In the servicing of electric generators, motors, and the like, it is conventional from time to time to remove the cover plates around the commutator and apply an abrasive stone to the surface of the commutat-or to remove the tarnished and corroded surface so that the commutator brushes will make better contact with .the commutator. To do this, one of the brush supports is removed and a grinding unit is substituted in its place in an accessible position. While the motor or generator is turned, a stone on the grinding unit is traversed across the surface of the commutator to remove the tarnished surface.

In the past, the dust that is created by this grinding operation has been allowed to fly free from the operation and has proved very detrimental. For example, it is not uncommon for this dust to cover and cake the studs that the brushes are mounted on and this will cause shorts if the user attempts to operate the unit without first cleaning its inside. Additionally, the grinder unit is manually operated and the flying dust is very uncomfortable and irritating to the operator. This irritation causes the operator to short cut his Work and he will also be tempted to stand as far `away as possible rather than hovering directly over the work and paying close attention to the grinding operation. This leads to an inefficient job and a sloppy resul-t.

Additionally, the flying dust will cover any adjacent equipment and machinery, and it has been necessary in the past to `cover any other equipment in the same compartment with a commutator that is being ground.

For this reason my invention is very important in that it is used to collect the dust that comes up from the grinding operation. The nozzle mechanism 66 is positioned just ahead of the stone in the direction of rotation as indicated by the arrow in Figure 3 so that the dust from the point of contact between the stone and the commutator Will be immediately picked up by the nozzle. I have found that this method will work very efficiently if the nozzle has approximately the same width as the commutator, although it can vary from it by an inch or so.

The nozzle should also be approximately the same width as the stone so that it will pick up and remove all of the dust created during the operation.

It is very important lthat the nozzle be positioned as close to the stone as it can, as shown in Figure 3, so that practically all of the dust will be picked up.

To improve the efficiency of the dust collecting operation, the brush 80 on the end of the nozzle contacts the small openings and cracks between the commutator elements and forces the dust and dirt out of them so that it will be picked up and collected by the second opening 86 while the rst opening 84 is picking up all of the loosely flying dust from the stone.

The attaching mechanism 98 shown for the nozzle may be any suitable type that will give the unit flexibility so that the nozzle can be positioned in different places. The clamps 102 and 106 are conventional `and any suitable types can be used which are adapted to adjustably connect two rods together.

It is lalso feasible to connect the nozzle to the stone carriage, so that as the stone is traversed back and forth, the nozzle Will go With it. This is particularly true in the case of very wide commutators, for example, on the order of 26 inches :or so, where a small brush is being used. In this case the nozzle should again be at least as wide, if not Wider than, the stone and it should move back and forth with the stone.

While I have shown and described a manually operated stone carriage, it should be understood that an automatic ings t0 be taken as in a broad sense illustrative or diagram-- matic, rather than as limiting me to my precise showing.

I claim:

l. In a commutator grinding unit, adapted to be used on a rotatably mounted commutator, a grinding unit adapted to be mounted on the commutator housing, said unit having a grinding stone adapted to engage the commutator, a source of suction, and a nozzle in communication with the source of suction adapted to be disposed behind the stone in the normal direction of rotation of the commutator so that substantially all of the dust created by the grinding operation will be removed by `the nozzle, the nozzle being generally spaced at all points from the surface of the commutator, the nozzle being approximately the same width as the stone, the nozzle including a brush element lixedly mounted and extending beyond the nozzle and adapted to engage the commutator under the nozzle intake so as to remove substantially all of the dust from the crevices in the commutator.

2. In a commutator grinding and cleaning unit adapted .to be used on a rotating commutator, a grinding unit adapted to rbe mounted on the commutator housing so as to bear against and grind the commutator, said unit having a grinding stone adapted to engage the commutator, a source of suction, and a nozzle in communication with the source of suction adapted to be disposed behind the stone in the direction of rotation of the commutator so that substantially all of the dust created by the grinding operation will be removed by the nozzle, the nozzle being generally spaced at all points from the surface of the commutator.

3. The structure of claim 2 in which the nozzle is primarily the same width as the stone.

4. A method of grinding a commutator including the steps of rotating the commutator, applying a grinding stone to the surface of the commutator while it is being rotated, and communicating a source of suction directly to the area -of the commutator behind the stone relative to its direction of rotation, and brushing the commutator directly in the area where the source of suction is applied 5. A method of grinding a commutator including the steps of rotating the commutator, applying a grinding stone to the surface of the commutator at a grinding area while it is being rotated, and communicating a source of suction directly to the grinding area of the commutator behind and adajcent the stone relative to the commutators direction of rotation.

6. A method of grinding a rotatably mounted commutator so as to eliminate substantially all dust, including the steps of rotating the commutator at a suitable speed, applying an abrasive element to the commutator in a localized grinding zone while it is being rotated to remove the commutators tarnishedsurface and subjecting the area of the commutator directly behind and adjacent the localized grinding zone in the commutators direction of rotation to a vacuuming source so as to simultaneously grind and remove substantially all dust created by the abrasive element.

7. A method of grinding a rotary electrical transfer unit, such as a commutator or the like, including the steps of rotating the unit, applying a grinding stone to the surface of the unit while it is being rotated, and communicating a source of suction directly to the area of the unit behind the stone relative to the units direction of rotation, and brushing the unit directly in the area where the source of suction is applied.

8. In a grinding and cleaning unit adapted to be used on a rotary electrical transfer device, such as a commutator or the like, a grinding unit adapted to be mounted on the housing of the electrical transfer device so as to bear against and grind the device, said unit having a grinding stone adapted to engage the device, a source of suction, and a nozzle in communication with the source of suction adapted to be disposed behind the stone in the direction of rotation of the rotary electrical transfer device so that substantially all of the dust created by the grinding operation will be removed by the nozzle, the nozzle being generally spaced at all points from the surface of the rotary electrical transfer device.

References Cited in the le of this patent UNITED STATES PATENTS 991,996 Hunt May 9, 1911 1,904,385 Poling Apr. 18, 1933 2,563,286 Snively Aug. 7, 1951 FOREIGN PATENTS 241,051 Germany Nov. 24, 1911 

